In connection with the completion of oil and gas wells, it is frequently necessary to utilize packers in both open and cased boreholes. The walls of the well or casing are plugged or packed from time to time for a number of reasons. As shown in FIG. 1, for example, sections of a well 10 may be packed off with packers 16 on a tubing string 12 in the well. The packers 16 isolate sections of the well 10 so pressure can be applied to a particular section of the well 10, such as when fracturing a hydrocarbon bearing formation, through a sliding sleeve 14 while protecting the remainder of the well 10 from the applied pressure.
In some situations, operators may prefer to utilize a comparatively long sealing element on the packer's 16. In these instances, as the sealing element is compressed longitudinally by a piston, friction and other forces combine to cause the sealing element to bunch up or otherwise bind near the piston. As a result, the longer sealing element does not uniformly compress in the longitudinal direction and by extension does not expand uniformly in the radial direction. The lack of uniform expansion tends to prevent the packer 16 from forming a seal that meets the operator's expectations, thereby defeating the purpose of utilizing a longer sealing element
Therefore, a significant need exists for a packer that is able to utilize an extended length sealing element.